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  <title>Document</title>
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<script>
  function getFactorial(Factorial) {
    var num
    for(var i = 1 ; i <= Factorial ; i++) {
      if(i === 1) {
        num = i * (i + 1)
      }else if(i !== 2){
        num *= i
      }
    }
    return num
  }

  console.log(getFactorial(4));

</script>
</html>
